Needs to find the motor serial number.
A 1977 911 was a 2.7liter.. with about 160hp
A genuine 2.0L "s" spec motor is 180hp and the early "s" registry folks would likely pay extra for it, vs a $1.5k 1977 motor.
A 2.0L non-s motor, kept stock, is closer to about 130hp
brown sure makes it look faster doesn't it
Late 1960s-1970s was a great time for Kit car manufacturers.. looks like all the others.. but I can't put a name/brand on it.